Term
| two fundamental concepts of chemistry |
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Definition
1. matter is composed of various types of atoms
2. one substance changes to another by reorganizing the way atoms are attached to each other |
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Term
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Definition
- natural law = summary of observed (measurable) behavior
- theory = attempt to explain behavior (why it happens) |
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Term
| fundamental SI units: mass, length, time, temperature, amount of substance, volume, electric current, luminous intensity |
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Definition
| kilogram (kg), meter (m), second (s), Kelvin (k), mole (mol), liter (L), ampere (A), candela (cd) |
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Term
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Definition
- mass = measure of the resistance of an object to a change in its state of motion
- weight = force that gravity exerts on an object |
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Term
| homogeneous vs. heterogeneous |
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Definition
- homogeneous = visibly INDISTINGUISHABLE parts --> solution
- heterogeneous = visibly DISTINGUISHABLE parts --> pure substance(constant composition) or 2+ solutions |
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Term
| methods to seperate components into mixtures |
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Definition
1. distillation
2. filtration
3. chromatography = stationary phase (solid), mobile phase (liquid or gas)
4. paper chromatography = stationary phase is paper |
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Term
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Definition
if given A±B(uncertainty),
percentage uncertainty = (B/A) x 100 |
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Term
calculating uncertainty
1. adding/subtracting
2. mutiplication/division
3. to a power |
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Definition
1. absolute uncertainties can be added
2. convert absolute uncertainty to percent uncertainties, then add
3. percent uncertainty times the power |
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Term
| What to do with sigfigs when ADDING percent uncertainties during multiplication/division of absolute uncertainties? |
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Definition
if added percent uncertainties are:
- greater than or equal to 2%, 1 sigfig
- less than 2%, no more than 2 sigfigs |
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Term
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Definition
| [(|actual - theoretical|) ÷ theoretical] x 100 |
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Term
| if % uncertainty > % error |
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Definition
- random errors
- instrument's fault
- more trials will help improve data |
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Term
| if % uncertainty < % error |
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Definition
- systematic errors
- your fault |
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Term
| Law of Conservation of Mass |
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Definition
- mass is neither created nor destroyed
- experiments showed combustion involved oxygen, not phlogiston
- Priestly, Lavoiser |
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Term
| Law of Definite Proportion |
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Definition
- a given compound always contains exactly the same proportion of elements by mass
- constant composition of compounds
- Proust |
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Term
| Law of Multiple Proportions |
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Definition
| - molecular formula can be reduced to emperical formula |
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Term
| Greeks questioned whether matter was: |
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Definition
1. continuous/infinitely divisible
2. composed of small, indivisible parts (Democritus of Abdera, Leucippos = coined the term atom) |
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Term
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Definition
| laid foundations of chemistry |
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Term
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Definition
| first chemist to perform truly quantitative experiments |
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Term
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Definition
1. each element is made up of tiny particles called atoms
2. the atoms of a given element are identical; the atoms of different elements are different in fundamental ways
3. chemical compounds formed when different elements combine
4. atoms themselves arent changed in chemical reaction, but reorganized |
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Term
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Definition
| same number of protons, different number of neutrons |
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Term
| if all atoms are composed of these same components, why do different atoms have different chemical properties? |
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Definition
| number and arrangement of electrons, therefore 3 of electrons possessed by given atom greatly affects its ability to interact with other atoms |
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Term
| properties of atom: mass, # of protons, # of neutrons, # of electrons, |
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Definition
| protons + neutrons, atomic #, mass - protons unless its an isotope, # of protons unless it has a charge |
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Term
| chemical vs covalent vs ionic BONDS |
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Definition
- forces that hold atoms together, in general
- share electrons... form molecules
- transfer electrons... opposites attract |
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Term
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Definition
| isotope that contains an unstable nucleus |
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Term
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Definition
| number of neutrons are too high or too low |
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Term
| all atoms over __ protons are radioactive |
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Definition
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Term
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Definition
- positively charged
- ionizing radiation: strips electrons off things they pass through
- can't pass through paper or large clothing
*4,2,He on right side |
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Term
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Definition
- negatively charged
- neutron decays to a proton and electron (N --> P+ + e-
- smaller than alpha, therefore better at ionizing than alpha
- cant pass through 3 mm aluminum foil
*0,-1,e on right side |
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Term
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Definition
- no charge
- not made of matter, PURE ENERGY = LOTS OF ENERGY, form of electromagnetic energy
- usually emitted after transmutation (nucleus changed)
- can't pass through 60 cm Al or 7 cm Pb
*0,0,Y on right side |
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Term
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Definition
- no charge
- proton is turned into neutron (P+ e- --> N)
- one of the inner-orbital electrons is captured by the nucleus
- *0,-1,e on left side |
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Term
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Definition
- positive charge
- instead of 0,-1,e it is 0,+1,e
- antimatter, destroyed when they encounter an electron
- electron + positron = 2 gamma rays
*0,+1,e on right side |
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Term
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Definition
collision caused a change in nucleus, the problems you solve the math to figure out blank elements and yadayada
- occurs in nuclear decay, fusion, and fission |
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Term
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Definition
| splitting a nucleus into 2 or more elements, some mass lost, breaks law of conservation of matter, chain reaction, e=mc^2 |
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Term
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Definition
| when 2 nuclei combine, lots of energy can be released, occurs in stars |
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Term
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Definition
| used to detect radioactive activity by measuring current that radiation produces in argon gas |
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Term
| Ammonium, Carbonate, Chlorate, Chromate, Hydrogen Carbonate (bi), Hydroxide, Nitrate, Permanganate, Phosphate, Sulfate |
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Definition
| NH4+, CO32-, ClO3-, CrO42-, HCO3-, OH-, NO3-, MnO4-, PO43-, SO42- |
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Term
| Relative Atomic Mass (Ar) |
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Definition
mass of a single atom relative to C-12....isotope
isotope mass / mass of carbon (which is 12) = Ar |
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Term
| Relative Molecular Mass (Mr) |
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Definition
| sume of the Ar in a molecule |
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Term
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Definition
| % mass of element = (mass of element/mass of compound) x 100 |
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Term
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Definition
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Term
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Definition
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Term
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Definition
| (actual yield/theoretical yield) x 100 |
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Term
| percent to mass mass to mole divide by small multiply till whole.... method used when? |
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Definition
| determining molecular/emperical formulas |
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Term
| grams to moles to moles to grams......method used when? |
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Definition
| stoichiometric caculations of limiting/excess reactants and products |
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Term
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Definition
instrument used to determine the masses of atoms and their isotopic composition by the deflection of ions in a magnetic field
vaporization, ionization, acceleration, deflection, detection
VIADD! |
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Term
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Definition
| 1. start with limiting ~ COMPARED TO ~ excess |
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Term
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Definition
| maximum amount of a product formed when limiting reactant is completely used up |
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Term
| to determine theoretical yield of a product |
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Definition
| start with limiting reactant ~ COMPARED TO ~ product calculating theoretical yield for |
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Term
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Definition
| unequal charge distribution |
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Term
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Definition
| + ends of water molecules attract to anions of ionic solid, and - ends of water molecules attract to cations of ionic solid |
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Term
| when ionic substances (salts) dissolve in water, they break up into _______ |
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Definition
| INDIVIDUAL cations and anions |
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Term
| when an ionic solid dissolves in water, ions become: |
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Definition
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